1. Field of the Invention
The present invention relates to a medical apparatus in which a raising base is disposed on a distal end side of an inserting portion and water tightness and air tightness are imparted to a pulling mechanism of the raising base housed in an operating section.
2. Description of the Related Art
In general, a treatment tool having various functions, e.g., a forceps is inserted into an endoscope main body and extended from an opening opened on a distal end side. For example, a treatment tool raising base is known in which an opening is disposed in a part of a peripheral surface side of a distal end of an endoscope main body, and a treatment tool such as a guide wire extended laterally from the opening is bent in a desirable direction.
The treatment tool raising base is revolved and bent by an operating section disposed on a proximal end side of an endoscope while supporting the guide wire, so that the treatment tool can be directed in the desirable direction of an operator. The operating section is coupled with the treatment tool raising base via a wire or the like inserted into a forceps raising tube path.
A treatment tool raising base portion is inserted and used in a body cavity, and hence after the portion is used, a washing treatment in the forceps raising tube path is performed. Therefore, as suggested in, for example, Jpn. Pat. Appln. KOKAI Publication No. H09-238898, an O-ring made of an elastic material is fitted the wire or a wire stopper to realize a watertight (or airtight) constitution so that a liquid such as a washing liquid does not invade the operating section of the endoscope through the tube path from the opening.
The abovementioned watertight constitution in the forceps raising tube path is realized by the O-ring, and hence, a sliding resistance between the wire and the O-ring increases. That is, the sliding resistance acts in a braking manner to an operation of an operating lever connected to the wire, and hence, the operation of the operating lever becomes heavy, and it is difficult for the operator to adjust an operating force, which becomes one reason why a delicate operation is hard to be performed. In addition, conversely, when the sliding resistance between the wire and the O-ring is decreased, water tightness and air tightness deteriorate, and there is the fear of a situation such as the invasion of the washing liquid into the operating section or the invasion of the liquid into the body cavity during the use.